Reciprocating internal combustion engines have a series of pistons reciprocating in appropriate cylinders. These pistons are connected to a crankshaft to translate the reciprocating movement to a rotary output. All reciprocating internal combustion engines have some degree of gases that pass by the pistons from the combustion chamber to an interior chamber for the engine, usually called the crankcase.
Internal combustion engines of the heavy duty diesel type, where the heat of intake air compression is used to ignite fuel that is injected by a fuel injection system at, or near the end of the compression stroke to provide combustion and a power output have greater issues with blowby gases. Such engines are typically turbocharged so that the charge at the beginning of the compression stroke can be above atmospheric pressure. This and other factors such as the normal high compression of the diesel engine cause blowby gases to pass from the cylinder past the piston into a crankcase that houses the crankshaft and other working mechanisms for the engine.
In the past, blowby gases have been vented directly to the atmosphere. The reason for this is that it is not possible to contain the gases in the crankcase because pressure would eventually build up and cause leakage through various seals and other gaskets.
Recent proposals in the emissions laws have mandated that blowby gas (also called crankcase ventilation gases) must be included as part of the regulated emissions. This means that any product of the fluids coming from the crankcase must be either treated or somehow dealt with. One approach has been to direct the blowby gas into the inlet of a turbocharger compressor so that the blowby gas is mixed with the fresh air and consumed by the combustion process of the engine. However, since the blowby gases have oil particles as well as unburned hydrocarbons, the entry of these gases into the compressor inlet can cause a deposit on the compressor. In cases where a high pressure ratio compressor is used for the turbocharger, the discharge temperature of the compressor may be high enough to cause coking.
Other manufacturers have used elaborate liquid separation and filtration devices to remove the emissions. Using filtration devices, requires periodic replacement which in turn increases the complexity and cost to maintain the engine. Even when the bypass flow is filtered, it does not completely eliminate the emissions of components of the bypass flow that are subject to regulation.
Thus, a need exists in the art to provide a cleaning of the fluids passing through the bypass flow passageway.